Ph.D. Program in Oceanography and Global Change at the Canary Islands, Spain
Coastal areas have been under pressure throughout history. Today these environments are occupied by a large portion of the world population and are dramatically affected by human activities. For a better understanding of the natural evolution of coastal ecosystems and their present state, historical studies are necessary. For this purpose researchers should apply methods that combine different historical sources, such as historic mapping and oral sources. In this dissertation the historical environmental conditions and land uses have been examined, and the causes that led to the disappearance and degradation of two coastal sedimentary systems of Canary Islands, Guanarteme dune field (Gran Canaria) and La Graciosa islands, respectively. Results reveal that (a) major landforms have changed both in shape and number, as well as the volume of sediments; (b) that each different land use had a different impact on the environment, and this was in correspondence with socio-economic needs in Guanarteme; and (c) the existence of six stages during which the intensity of human pressure on the human-environment relationship changed in La Graciosa.
